Beta 1.3

Changes:

• added copper and tin ores
• the copper ore has a sand variant that can be broken by hand, but will give less actual copper
• explosions have a chance of dropping destroyed blocks as items
• cacti can now grow up to seven blocks tall. It is very slow however.
• replaced the level to image renderer with a new one, based on Raylib's Image functions. This one is about ten times faster than the old one
• items disappear after fifteen seconds
• player's speed is now correctly enforced depending on the gamemode
• decrease ore spawn rates
• removed restrictions over where one can place blocks in creative mode
• fixed being able to hover and/or break blocks in some UI screens

This update introduces level format 14, which is incompatible with the previous one.

This is the first version released during holidays! Yay!